This invention relates to structures for mounting electrical devices, and more particularly, to multi-layer, laminated structures on which electrical devices may be mounted, to methods for fabricating such structures, and to power supplies including such structures.
Many systems employ electrical devices. It is often desirable to densely pack these devices so as to reduce the size of the system. Indeed, the ability to do so can be essential to meeting the demand for systems having smaller packages and ever increasing power densities.
As a result, electrical devices are often mounted on printed circuit boards, which use printed circuitry rather than discrete wires. Where the number of electrical devices in a system demands, multiple printed circuit boards are employed. Some systems stack such printed circuits boards, one on top of one another, in order fit them all within the system.
One drawback associated with the stacking of printed circuit boards is that the spacing between the boards is often dictated by the dimensions of the tallest devices on the boards. Consequently, unless all of the devices on a particular board have the same height, at least a portion of the volume between adjacent boards is unused and thus wasted.
Another drawback associated with the stacking of printed circuit boards is that connectors are often needed to electrically connect one printed circuit board to another. The need for such connectors adds size, weight, labor and cost to the system.
Flexible substrates are sometimes employed in place of connectors to solve the connector issue, however, flexible substrates do not solve the issue of unused volume between boards.
Accordingly, it is an object of the present invention to provide laminated structures for mounting electrical devices and methods of making such structures that overcome one or more of the above described drawbacks of the prior art.
According to a first aspect of the present invention, a circuit includes a multi-layer laminate having a first portion and a second portion. The first portion has a first major surface on which at least one electrical device is mounted. The second portion is attached to the first portion and folded so as to provide at least one substantially planar portion that overlays a fractional portion of the first major surface of the first portion and on which at least one electrical device is mounted.
According to another aspect of the present invention, a circuit includes a multi-layer laminate having a first portion with a first major surface on which at least one electrical device is mounted. The laminate further includes means for providing at least one substantially planar portion that overlays a fractional portion of the first major surface of the first portion and on which one or more electrical devices may be mounted and electrically connected to, said means being attached to the first portion and folded.
According to another aspect of the present invention, a method for forming an assembly includes providing a multi-layer laminate having first portion a second portion attached to the first portion. The first portion has a first major surface on which one or more electrical devices may be mounted. The method further includes folding the second portion so as to provide at least one substantially planar surface that overlays a fractional portion of the first major surface of the first portion and on which one or more electrical devices may be mounted.
According to another aspect of the present invention, a circuit includes a multi-layer laminate having a base portion and at least one second portion. The base portion has a first major surface adapted to receive one or more electrical devices to be mounted thereon. The at least one second portion extends from a marginal portion of the base portion and defines a folded portion overlying a fractional portion of the first major surface of the base portion, and on which at least one electrical device is mounted.
According to another aspect of the present invention, a circuit includes a multi-layer laminate having a base portion with a first major surface adapted to receive one or more electrical devices to be mounted thereon. The multi-layer laminate further includes first means extending from a marginal portion of the base portion for overlying a fractional portion of the first major surface of the base portion and mounting at least one electrical device thereto.
According to another aspect of the present invention, an assembly includes a multi-layer laminate having a first portion and a second portion. The first portion has a first major surface on which at least one electrical device is mounted. The second portion is attached to the first portion and is adapted to receive at least one electrical device, and includes means for positioning the at least one electrical device to be mounted on the second portion within a volume that overlays a fractional portion of the first major surface of the first portion.
According to other aspects of the present invention, a power supply includes a circuit in accordance with one or more of the above aspects.
One advantage of the currently preferred embodiments of the present invention is that they provide a substantially planar surface that overlays only a fractional portion of another circuit thereby making it possible to xe2x80x9cpackxe2x80x9d electrical devices into areas that might otherwise be unused (e.g., above components that are relatively short). As a result, more devices can be packed into a given volume, thereby helping to achieve a desired power density. In addition, in at least some embodiments, the devices mounted on the substantially planar surface of the substantially flexible circuit can be electrically connected by way of the flexible circuit, thereby avoiding the need to add additional connectors, along with the added weight, labor and cost typically associated with adding connectors.
Other advantages of the multi-layer laminate and method of the present invention will become apparent in view of the following detailed description of preferred embodiments, claims, and accompanying drawings.